package ingest

import (
	"encoding/json"
	"fmt"
	"os/exec"
	"time"
)

type GiteaIngester struct {
	Version string
}

func NewGiteaIngester() *GiteaIngester {
	return &GiteaIngester{Version: "gitea-tea/v1"}
}

func (g *GiteaIngester) SourceID() string { return "gitea" }

func (g *GiteaIngester) IngestAll() ([]*IngestResult, error) {
	var results []*IngestResult

	repos, err := g.fetchRepos()
	if err == nil {
		for _, r := range repos {
			if result := g.repoToResult(r); result != nil {
				results = append(results, result)
			}
		}
	}

	issues, err := g.fetchIssues()
	if err == nil {
		for _, i := range issues {
			if result := g.issueToResult(i); result != nil {
				results = append(results, result)
			}
		}
	}

	pulls, err := g.fetchPulls()
	if err == nil {
		for _, p := range pulls {
			if result := g.pullToResult(p); result != nil {
				results = append(results, result)
			}
		}
	}

	return results, nil
}

type teaRepo struct {
	Owner       string `json:"owner"`
	Name        string `json:"name"`
	Description string `json:"description"`
	Updated     string `json:"updated"`
}

type teaIssue struct {
	Index   string `json:"index"`
	Title   string `json:"title"`
	State   string `json:"state"`
	Owner   string `json:"owner"`
	Repo    string `json:"repo"`
	Labels  string `json:"labels"`
	Author  string `json:"author"`
	Updated string `json:"updated"`
}

type teaPull struct {
	Index   string `json:"index"`
	Title   string `json:"title"`
	State   string `json:"state"`
	Owner   string `json:"owner"`
	Repo    string `json:"repo"`
	Updated string `json:"updated"`
}

func (g *GiteaIngester) teaJSON(args ...string) ([][]byte, error) {
	cmd := exec.Command("tea", append(args, "--output", "json")...)
	output, err := cmd.Output()
	if err != nil {
		return nil, fmt.Errorf("tea %s: %w", args[0], err)
	}

	var raw json.RawMessage
	if err := json.Unmarshal(output, &raw); err != nil {
		return nil, err
	}

	// Handle both array and object responses
	var arr []json.RawMessage
	if err := json.Unmarshal(raw, &arr); err == nil {
		bytes := make([][]byte, len(arr))
		for i, a := range arr {
			bytes[i] = a
		}
		return bytes, nil
	}

	// Single object — wrap in array
	return [][]byte{raw}, nil
}

func (g *GiteaIngester) fetchRepos() ([]teaRepo, error) {
	items, err := g.teaJSON("repos", "list", "--limit", "100", "--fields", "owner,name,description,updated")
	if err != nil {
		return nil, err
	}
	var repos []teaRepo
	for _, item := range items {
		var r teaRepo
		if err := json.Unmarshal(item, &r); err == nil {
			repos = append(repos, r)
		}
	}
	return repos, nil
}

func (g *GiteaIngester) fetchIssues() ([]teaIssue, error) {
	items, err := g.teaJSON("issues", "list", "--state", "open", "--limit", "100", "--fields", "index,title,state,author,milestone,labels,owner,repo,updated")
	if err != nil {
		return nil, err
	}
	var issues []teaIssue
	for _, item := range items {
		var i teaIssue
		if err := json.Unmarshal(item, &i); err == nil {
			issues = append(issues, i)
		}
	}
	return issues, nil
}

func (g *GiteaIngester) fetchPulls() ([]teaPull, error) {
	items, err := g.teaJSON("pulls", "list", "--state", "open", "--limit", "100", "--fields", "index,title,state,owner,repo,updated")
	if err != nil {
		return nil, err
	}
	var pulls []teaPull
	for _, item := range items {
		var p teaPull
		if err := json.Unmarshal(item, &p); err == nil {
			pulls = append(pulls, p)
		}
	}
	return pulls, nil
}

// signalTime returns the item's last-activity time, or "" when unknown. An
// empty value is an explicit unknown — downstream uses it as a missing signal,
// never fabricates a "now" timestamp that would differ across nodes.
func signalTime(updated string) string {
	if updated != "" {
		if _, err := time.Parse(time.RFC3339, updated); err == nil {
			return updated
		}
	}
	return ""
}

func (g *GiteaIngester) repoToResult(r teaRepo) *IngestResult {
	fullName := r.Owner + "/" + r.Name
	fp := Fingerprint([]byte("gitea:repo:" + fullName))

	return &IngestResult{
		Fingerprint:     fp,
		SourceID:        g.SourceID(),
		SourcePath:      fullName,
		Project:         r.Name,
		ContentType:     "repo",
		Title:           fullName,
		Summary:         r.Description,
		Confidence:      0.9,
		IngesterVersion: g.Version,
		CreatedAt:       signalTime(r.Updated),
		Provenance: map[string]any{
			"type":        "repository",
			"owner":       r.Owner,
			"name":        r.Name,
			"description": r.Description,
		},
	}
}

func (g *GiteaIngester) issueToResult(i teaIssue) *IngestResult {
	title := fmt.Sprintf("#%s %s", i.Index, i.Title)
	fp := Fingerprint([]byte(fmt.Sprintf("gitea:issue:%s/%s:%s", i.Owner, i.Repo, i.Index)))

	summary := fmt.Sprintf("[%s/%s#%s] %s", i.Owner, i.Repo, i.Index, i.Title)
	if i.Labels != "" {
		summary += " [" + i.Labels + "]"
	}

	return &IngestResult{
		Fingerprint:     fp,
		SourceID:        g.SourceID(),
		SourcePath:      fmt.Sprintf("%s/%s#%s", i.Owner, i.Repo, i.Index),
		Project:         i.Repo,
		ContentType:     "issue",
		Title:           title,
		Summary:         summary,
		Confidence:      0.85,
		IngesterVersion: g.Version,
		CreatedAt:       signalTime(i.Updated),
		Provenance: map[string]any{
			"type":   "issue",
			"owner":  i.Owner,
			"repo":   i.Repo,
			"index":  i.Index,
			"state":  i.State,
			"labels": i.Labels,
		},
	}
}

func (g *GiteaIngester) pullToResult(p teaPull) *IngestResult {
	title := fmt.Sprintf("!%s %s", p.Index, p.Title)
	fp := Fingerprint([]byte(fmt.Sprintf("gitea:pull:%s/%s:%s", p.Owner, p.Repo, p.Index)))

	return &IngestResult{
		Fingerprint:     fp,
		SourceID:        g.SourceID(),
		SourcePath:      fmt.Sprintf("%s/%s!%s", p.Owner, p.Repo, p.Index),
		Project:         p.Repo,
		ContentType:     "pull",
		Title:           title,
		Summary:         fmt.Sprintf("[PR %s/%s] %s", p.Owner, p.Repo, p.Title),
		Confidence:      0.85,
		IngesterVersion: g.Version,
		CreatedAt:       signalTime(p.Updated),
		Provenance: map[string]any{
			"type":  "pull_request",
			"owner": p.Owner,
			"repo":  p.Repo,
			"index": p.Index,
			"state": p.State,
		},
	}
}

func (g *GiteaIngester) Ingest(_ string) (*IngestResult, error) {
	return nil, fmt.Errorf("use IngestAll() for gitea")
}

var _ Ingester = (*GiteaIngester)(nil)